JP2502565B2 - Vehicle power transmission device - Google Patents

Description

TECHNICAL FIELD The present invention relates to an improved technique of a power transmission device that transmits power from an engine to front wheels or rear wheels of a vehicle.

(Prior Art) Conventionally, as an example of a vehicle power transmission device of this type, for example, JP-A-57-87716 and U.S. Pat.
As shown in Japanese Patent Laid-Open Publication No. 2005-242242, an engine and a transmission are so-called laterally supported laterally in the front and rear of the vehicle body, and an input member is provided on an axle shaft located on the engine side (transmission side). As a sprocket,
A differential mechanism (differential mechanism) composed of a bevel gear mechanism connected to the sprocket via a speed reduction mechanism composed of a planetary gear mechanism.
It is known that the sprocket on the axle shaft is drive-connected to the output sprocket of the transmission by a chain.

(Problems to be Solved by the Invention) By the way, when a reduction gear mechanism such as a planetary gear mechanism is arranged on the input side of the axle shaft as in this conventional example, side gears, pinions, etc. constituting the reduction gear mechanism are generally used. Helical gear is adopted. However, in a reduction gear mechanism using this helical gear, thrust force is generated in the axial direction of the axle.Therefore, in order to receive this thrust force, it is possible to leave a slight space for the reduction gear mechanism to the side sprockets and differential mechanism. Done. Therefore, the length of the power transmission device in the axial direction of the axle becomes longer by the amount of the space, which makes it difficult to make the power transmission device compact.

Further, since the diff mechanism, the speed reducing mechanism and the sprocket are arranged in the separated state in this way, when the device is assembled, the diff mechanism, the speed reducing mechanism and the sprocket are individually assembled to the axle shaft. There was also the problem of poor assembly of the device.

The present invention has been made in view of the above points, and an object thereof is to improve a reduction mechanism by improving a reduction mechanism arranged on the axle shaft and a support structure of an input member including a sprocket and a gear. The length of the power transmission device in the axial direction of the axle is shortened regardless of the action of the thrust force in the axial direction, and the support structure of the input member and the reduction mechanism is simplified to improve the assembling property of the device. It is in.

(Means for Solving the Problems) In order to achieve this object, the solving means of the present invention supports a speed reducing mechanism including an input member and a planetary gear mechanism on the differential mechanism arranged on the axle shaft. Bearings are arranged between the differential mechanism and the input member, and between the input member and the reduction mechanism.

More specifically, the present invention is directed to a power transmission device for a vehicle in which an engine and a transmission are supported by a front portion or a rear portion of a vehicle body with output shafts thereof arranged in the lateral direction of the vehicle body.

An input member such as a gear or a sprocket that is drivingly connected to an output member of the transmission is provided on an axle shaft that is located on a side where the engine and the transmission are supported, and a reduction mechanism including a planetary gear mechanism for the input member. A differential mechanism connected via the differential mechanism is provided, and the input member and the reduction mechanism are supported by the differential mechanism.

Further, thrust bearings are arranged between the input member and the speed reducing mechanism and between the input member and the differential mechanism, respectively, and on the other hand, between the connecting portion between the input member and the speed reducing mechanism and the differential mechanism. Is equipped with a radial bearing.

(Operation) With this configuration, in the present invention, the thrust bearings are respectively arranged between the input member and the reduction mechanism arranged on the axle shaft, and between the input member and the differential mechanism, while the input bearing is arranged. Since the radial bearing is arranged between the connecting portion between the member and the speed reducing mechanism and the differential mechanism, the gear element of the speed reducing mechanism is configured by a helical gear,
Even if the thrust force in the axial direction of the axle acts on the reduction mechanism, the thrust force can be received by the thrust bearing. Therefore, it is not necessary to provide a space between the reduction mechanism and the input member and the differential mechanism on the side of the reduction mechanism, so that the length of the power transmission device in the axle axis direction can be shortened and the power transmission device can be made compact. .

Further, since the input member and the speed reducing mechanism are supported by the differential mechanism via the radial bearing, the supporting structure of the input member and the speed reducing mechanism is simplified, and when the device is assembled, the input member and the speed reducing mechanism are previously attached to the differential mechanism. By assembling the speed reduction mechanism and the input member, they can be unitized, and therefore, the assemblability of the power transmission device can be improved.

(Example) Hereinafter, the Example of this invention is described based on drawing.

FIG. 2 is a plan view of an FF type vehicle according to an embodiment of the present invention, in which 1 is a vehicle body and 2 is a crankshaft at a front portion of the vehicle body 1.
A four-cylinder engine 2a (output shaft) mounted horizontally so that it extends in the left-right direction of the vehicle body, and 3 is an automatic transmission with a lock-up mechanism supported laterally on the left side of the engine 2. The transmission 3 includes an input shaft 6 connected to a crankshaft 2a of an engine 2 via a torque converter 5 in a housing 4, and a sprocket 7 as an output member externally fitted and supported by the input shaft 6. And a speed change mechanism 8 including a planetary gear mechanism for switching a power transmission path between the input shaft 6 and the sprocket 7, and wet clutch mechanisms 9 to 13 and a brake mechanism 14 for operating and adjusting the speed change mechanism 8. The gear ratio is switched by switching the transmission path between the input shaft 6 and the sprocket 7.

An axle unit 15 is provided on the rear side of the transmission 3. This axle unit 15 is an axle housing
A left and right axle shafts 17a, 17b are provided in the axle housing 16 in parallel with the crankshaft 2a of the engine 2 (the input shaft 6 of the transmission 3). The axle shafts 17a, 17b are connected to the left and right front wheels 20a, 2 via joints 18, 18 ... and left and right drive shafts 19a, 19b, respectively.
It is connected to 0b (driving wheel).

On the left and right axle shafts 17a and 17b, as shown in enlarged detail in FIG. 1, a differential mechanism 21 (differential mechanism) composed of a bevel gear mechanism, a speed reduction mechanism 26 composed of a planetary gear mechanism, and the above-mentioned speed change A sprocket 31 as an input member, which is drivingly connected to a sprocket 7 of the machine 3 via a chain 32, is arranged. The diff mechanism 21 is a hollow spherical diff case 22 that is externally fitted and supported by the left and right cylindrical support portions 22a and 22b on the left and right axle shafts 17a and 17b, respectively. A pair of side gears 23, 23 coupled to the inner ends of the axle shafts 17a, 17b, and a pinion shaft 2 meshed with the side gears 23 and arranged at right angles to the axle shafts 17a, 17b.
A pair of pinions 25, 25 rotatably supported by the differential case 22 by 4 are provided.

The left side support portion 22a of the differential case 22 extends leftward along the left axle shaft 17a, and the reduction mechanism 26 is supported on the left side support portion 22a. This reduction mechanism 26
Is a sun gear 27 supported by the left side support portion 22a of the differential case 22, and a plurality of pinions 28, 28, 28
... and a pinion carrier 29 carrying the respective pinions 28
And a ring gear 30 that meshes with each pinion 28. The ring gear 30 is non-rotatably spline-coupled to the inner wall of the axle housing 16. Further, the pinion carrier 29 has the inner peripheral tooth portion 29a at which the differential mechanism 2 is provided.
The outer peripheral surface of the differential case 22 is spline-coupled integrally with the differential case 22, so that the rotation input to the sun gear 27 in the reduction mechanism 26 is transmitted to the differential mechanism 21 while decelerating via the pinions 28, 28 ,. Has been done.

The sun gear 27 of the speed reduction mechanism 26 is extended leftward, and the sprocket 31 is fixed to the tip of the extended portion so as to rotate integrally. Further, a retaining ring 33 is integrally fixed on the left side support portion 22a of the differential case 22 on the left side of the sprocket 31, and the reduction mechanism 26 and the sprocket 31 are connected to the differential mechanism 21 by the retaining ring 33.
It is secured to the differential case 22 so as not to move in the axial direction.

The sprocket 31 and the pinion carrier 29 of the speed reduction mechanism 26 are opposed to each other between their opposing side surfaces, and the sprocket
Thrust bearings 34 and 35, which are needle bearings, are disposed between the opposing side surfaces of the 31 and the retaining ring 33 integrally fixed to the differential case 22 of the differential mechanism 21, respectively. Sprocket for differential mechanism 21 and reduction mechanism 26 by 34, 35
It is designed to regulate the relative movement of 31 in the axial direction.
On the other hand, the inner peripheral surface of the connecting portion between the sun gear 27 and the sprocket 31 of the reduction mechanism 26 and the differential case 22 of the differential mechanism 21.
A radial bearing 36, which is a needle bearing, is disposed between the outer peripheral surface of the support portion 22a of the differential gear 22 and the sun gear 27 of the reduction gear mechanism 26 and the sprocket 31 integrated with the sun gear 27 of the differential gear mechanism 22. It is designed to be rotatably supported with respect to.

Therefore, in the above embodiment, after the power output from the engine 2 is changed in rotation by the transmission 3,
It is transmitted from the sprocket 7 of the transmission 3 to the sun gear 27 of the speed reduction mechanism 26 via the chain 32 and the sprocket 31 on the axle shafts 17a and 17b, and after the rotation is reduced in the speed reduction mechanism 26, the differential mechanism 21 and the axle shaft 17a. , 17b and drive shafts 19a, 19b to the left and right front wheels 20a, 20b.

In this case, between the sprocket 31 and the pinion carrier 29 of the reduction mechanism 26, and between the sprocket 31 and the differential mechanism.
Thrust bearings 34 and 35 are arranged between the 21 diff case 22 (the retaining ring 33 that is integral with the diff case 22), so that the sun gear 27 of the reduction mechanism 26, the pinion 28, and the like are configured as helical gears. Even if a thrust force in the direction of the axle shafts 17a, 17b acts on the speed reduction mechanism 26, the thrust force can be received by the thrust bearings 34, 35. As a result, the sprocket 31 and the reduction mechanism 26 can be arranged close to each other, the length of the axle unit 15 in the direction of the axle shafts 17a, 17b can be shortened, and the power transmission device can be made compact.

Further, since the sprocket 31 and the speed reduction mechanism 26 are supported on the differential case 22 of the differential mechanism 21 via the radial bearing 36, the support structure of the sprocket 31 and the speed reduction mechanism 26 becomes extremely simple and they are integrated. It can be made into a unit, so that the assembling property of the axle unit 15 and by extension, the power transmission device can be enhanced. Moreover, such a sprocket 31 and the differential case of the reduction mechanism 26
The support on the 22 allows them to be centered automatically during assembly.

Furthermore, since the pinion carrier 29 of the speed reduction mechanism 26 is spline-coupled to the differential case 22 of the differential mechanism 21 and can be moved by a slight amount in the radial direction of the axle shafts 17a, 17b, the pinion carrier 29 is automatically moved. Can be centered, sun gear 27 and ring gear 30 on each pinion 28
The tooth contact with respect to can always be adjusted well.

Incidentally, in the above embodiment, the power from the transmission 3 is transferred to the chain.
Although the power is transmitted to the sprocket 31 on the front axle shafts 17a and 17b via 32, the power can be changed to be transmitted via the gear mechanism.

Further, in the above embodiment, the case where the invention is applied to the FF type vehicle in which the engine 2 and the transmission 3 are mounted on the front portion of the vehicle body 1, but the present invention is the RR type in which the engine and the transmission are at the rear portion of the vehicle body. Needless to say, it can also be applied to the above vehicles.

(Effects of the Invention) As described above, according to the present invention, an FF in which an engine and a transmission are mounted on a vehicle body in a so-called horizontal orientation or
In an RR type vehicle, an input member such as a sprocket that is drivingly connected to an output shaft of a transmission, a speed reduction mechanism including a planetary gear mechanism, and a differential mechanism are arranged on the axle shaft located on the engine side. At the same time, the input member and the speed reducing mechanism are supported by a differential mechanism, and thrust bearings are respectively provided between the input member and the speed reducing mechanism and between the input member and the differential mechanism, while the input member and the speed reducing mechanism are provided. By arranging the radial bearing between the connecting part and the differential mechanism, even if each gear element of the reduction mechanism on the axle shaft is composed of a helical gear, the thrust force to the reduction mechanism is generated by the thrust bearing. receive,
The speed reduction mechanism can be placed close to the input member and the differential mechanism, shortening the length of the power transmission device in the axle axis direction,
In addition to making it compact, by supporting the input member and the speed reduction mechanism to the differential mechanism, the supporting structure can be simplified and they can be integrated into one unit, and the assemblability of the power transmission device can be improved. It is possible.

[Brief description of drawings]

The drawings show an embodiment of the present invention, FIG. 1 is an enlarged cross-sectional view of a main portion, and FIG. 2 is a skeleton diagram showing an overall configuration of a power transmission system in a vehicle. 1 ... Body, 2 ... Engine, 3 ... Transmission, 7 ... Sprocket, 15 ... Axle unit, 17a, 17b ... Axle shaft, 20
a, 20b ... front wheel, 21 ... differential mechanism, 22 ... differential case, 26 ... reduction mechanism, 29 ... pinion carrier, 31 ... sprocket, 32
… Chain, 34,35… Thrust bearing, 36… Radial bearing.

Claims (1)

(57) [Claims] 1. A power transmission device for a vehicle, in which an engine and a transmission are supported on a front portion or a rear portion of a vehicle body by arranging respective output shafts thereof in a lateral direction of the vehicle body, the engine and the transmission being supported. An input member such as a gear and a sprocket that is drivingly connected to an output member of the transmission, and a differential mechanism that is connected to the input member via a speed reduction mechanism including a planetary gear mechanism are provided on the axle shaft located on the upper side. Is arranged,
The input member and the speed reducing mechanism are supported by a differential mechanism, and thrust bearings are respectively provided between the input member and the speed reducing mechanism and between the input member and the differential mechanism, while the input member and the speed reducing mechanism are provided. A power transmission device for a vehicle, wherein a radial bearing is arranged between a connecting portion with the reduction mechanism and the differential mechanism.